magnet.js

document.addEventListener("DOMContentLoaded", () => {
    const uhash = new URLSearchParams(location.search).get('hash');
    const thash = new URLSearchParams(location.hash.replace(/^#/, '')).get('hash');
    if(thash || uhash){
        document.getElementById('hash').value = thash || uhash;
        let urlr = update();
        if(urlr){
            window.location.href = urlr;
        }
    }
});

function encUri(text){
    return encodeURIComponent(text);
}

function sel_all(el){
    el.focus();
    el.select();
}

function update(){
    try{
        const hash_data = document.getElementById('hash').value;
        let uri = location.protocol + '//' + location.hostname + location.pathname;
        if(checkHash(hash_data)){
            let data  = 'magnet:';
                data += '?xt=urn:btih:' + encUri(document.getElementById('hash').value);
                // --
                data += '&tr=' + encUri('http://nyaa.tracker.wf:7777/announce');
                data += '&tr=' + encUri('udp://tracker.coppersurfer.tk:6969/announce');
                data += '&tr=' + encUri('udp://tracker.opentrackr.org:1337/announce');
                data += '&tr=' + encUri('udp://9.rarbg.to:2710/announce');
                data += '&tr=' + encUri('udp://9.rarbg.me:2710/announce');
                data += '&tr=' + encUri('udp://tracker.leechers-paradise.org:6969/announce');
                data += '&tr=' + encUri('udp://tracker.internetwarriors.net:1337/announce');
                data += '&tr=' + encUri('udp://tracker.cyberia.is:6969/announce');
                data += '&tr=' + encUri('udp://exodus.desync.com:6969/announce');
                data += '&tr=' + encUri('udp://tracker3.itzmx.com:6961/announce');
                data += '&tr=' + encUri('udp://tracker.torrent.eu.org:451/announce');
                data += '&tr=' + encUri('udp://tracker.tiny-vps.com:6969/announce');
                data += '&tr=' + encUri('udp://retracker.lanta-net.ru:2710/announce');
                data += '&tr=' + encUri('http://open.acgnxtracker.com:80/announce');
                data += '&tr=' + encUri('wss://tracker.openwebtorrent.com');
                // --
                data += '&tr=' + encUri('http://tracker.internetwarriors.net:1337/announce');
                data += '&tr=' + encUri('http://tracker.opentrackr.org:1337/announce');
                data += '&tr=' + encUri('udp://tracker.zer0day.to:1337/announce');
                data += '&tr=' + encUri('udp://tracker.pirateparty.gr:6969/announce');
                data += '&tr=' + encUri('http://explodie.org:6969/announce');
                data += '&tr=' + encUri('http://p4p.arenabg.com:1337/announce');
                data += '&tr=' + encUri('http://mgtracker.org:6969/announce');
            document.getElementById('link').href = data;
            document.getElementById('link_text').value = data;
            uri += '#hash='+hash_data;
            return data;
        }
        return false;
    }
    catch(e){
        alert('exception: ' + e);
        return false;
    }
}

function checkHash(hash){
    return hash.length == 32 && hash.match(/^[2-7A-Za-z]+$/) || hash.length == 40 && hash.match(/^[0-9A-Fa-f]+$/) ? hash : false;
}